Fuse-cartridge.



F. J. FERRARI. FUSHGARTRIDGE. APPLIGATION FILED MAY 81, 1911.

1,054,965 Patented Mar.4,1913.

UNITED STATES PATENT OFFICE.

FREDERICK J. FERRARI, or SYRACUSE, NEW YoRK'.

FUSE-CARTRIDGE.

Specification of Letters Iatent.

T 0 all whom it may concern:

.Be it known that I, FREDERICK J. FERRARI, of Syracuse, in the county ofOnondaga, in the State of New York, have invented new and usefulImprovements in Fuse-Cartridges, of which the following, taken inconnection with the accompanying drawings, is a full, clear, and exactdescription.

This invention relates to certain improvements in fuse holders, commonlyknown as cartridges, adapted to be removably inserted between .thespring fingers or contact terminals of electric circuit-s for receivingand concealing. fuse wires or bars of such circuits.

Heretofore so far as I am aware, the fuse supports have always beenpermanently incorporated in the cartridge or tube in such manner that ithas been impossible to remove the fuse support for .replacing the Iburned out fuses without destroying the entire cartridge, thereby makingit necessary to supply the entire cartridge when the fuse burned out orfailed from any cause to perform its function as a conducting part ofthe electric circuit.

. bodymg The main object, therefore, of my present invention is toemploy a fuse cartridge having the same general external appearance andutility as that now in common use in which the fuse supporting elementis removable from the shell or inclosing case to permit the fuse to beinspected or replaced without injuring the shell or in anyway detractingfrom the safety or efficiency of the cartridge. In other words I havesought to provide a simple, practical and eflicient fuse cartridgecapable of being used in connection with any of the switch boards towhich the ordinary cartridges are now applied with the additionaladvantage that the fuse holder may be easily and quickly removed forinspection or replacement of the fuse and then reinserted in the shellwith the assurance that it will afford as efiicient fire protection andsafety against accident as any of the cartridges heretofore employed.

Other objects and uses relating to specific parts of the device willbe'brought out in the following description;

In the drawings Figure 1 is an elevation, partly in section, of a fusecartridge enithe various features of my invention. 1g. 2 is a similarelevation of the detached fuse holder omitting the tubular shell orcasing. Figs. 3 and 4 are transyerse sectional views taken respect velyon lmes 3-3,

Fig. 1 and 44, Fig. 2. Fig. 5 is a longitudinal sectional view' of oneof the end ferrules for the outer shell or casing showing particularlythe groove for the bayonet lock. Fig. 6 is a longitudinal sectional viewof a modified form of shell. Fig. 7 is an elevation of a fuse holderadapted to be used in connection with the shell shown in Fig. 6. Fig. 8is a longitudinal sectional view through the other end ferrule for theouter shell or casing.

The cartridge shown in Figs. 1 to 5 inclusive comprises an outer tubularshell or casing 1 and a fuse holder 2- for supporting a fuse wire or bar3, and suitable contact plates -4 which are adapted to be insertedbetween spring terminals 5- shown by dotted lines in Fig. l and forminga part of an electric circuit, not shown, of which the fuse wire is toform a part. -The outer shell or casing -1 pref erably comprises a tube6 of vulcanized fiber or other suitable insulating material having aninner lining -7 of asbestos or equivalent heat resisting substance. endsof the insulating tube -6 and its lining 7 are inclosed in sheet metalferrules -8- 8' having relatively short inturned flanges ,9 integraltherewith. These ferrules perform the-- double function of binding orreinforcing the ends of the tube -6 and its lining -7-' andalso formingconductors adapted to engage the usual spring terminals of an electriccircuit,

not shown, for connecting the fuse wire in provided withsuitable bindingosts -12- for securing the ends of'the se wire or Patented Mar. 4:,1913.

The

bar 3 thereto. The ends of the insulating bar 10 and ferrules or rings-11--- secured thereto are preferably circular in cross section,whilethe intermediate portion of the bar is substantially semi-circular,thereby forming a recess in one side'of the fuse holder within which thefuse -3 and its bindingposts '-12- are located.

The contact bars'--4- are shown'asintegral with or electricallyconnected to the ferrules -l l-. which latter are adapted to engage witha close sliding fit with theinturned flanges -Q- -of the ferrulestubular casing 1 against accidentalen l; W1S8 displacement, I provide atleast one end of the fuse holder with a radially projecting stud --13-which isadapted to enter an inclined slot -14 in the adjacent flange 9of the ferrule S when the parts of the cartridge are assembled, therebyestablishing a bayonet lock between the fuse holder and outer shell orcasing and permitting these parts to be readily interlocked and removedendwise one from the other when necessary, the ferrule 8 being providedin its flangef9 with a lengthwise slot 8 which permits thepassage ofthestud, v

13. In some 1nstances,' ascin the smaller sized cartridges, the contactplates 4 may be omitted and the ferrules -8- brought into direct contactwith the spring terminals of the electric circuit commonly employed forretaining the cartridge in place.

In Figs. 6 and 7, I have shown a slightly modified form of cartridgecomprising an outer shell or casing 20 and a fuse holder -21-, the endsof the shell being inclosed in suitable ferrules -22 having inturnedflanges 23- for sliding contact with coacting ferrules 24 on the ends ofthe holder -21. The inner ends of the inner flanges -23 of the shell orcasing 2 are preferably crin ped outwardly so as to afford a freerpassage of the fuse holder into and out of the shell and at the sametime to allow closer contact between the ferrules 24 and flanges 23-.The ferrules 24 are mounted upon the ends of an insulating bar 25similar to the bar .10 and are electrically connected to each other by afuse wire or bar 26-yand suitable binding posts 27.

iii

The fuse holder shown in Fig. 7 may be removably inserted in either endof the shell 20 and is provided at one end with an annular knurledshoulder r-28 serving as a hand piece by which the fuse holdermay beinserted into and withdrawn from the outer shell.

.fls shown in Fig. 3, the ferrule -8- ala firmly crimped over and uponthe end of the" insulating tube 6- and its linang 7 may be additionallyheld in place by one or more pins -29, .while the. ferrules -8'- 11 and2-lfl maybe similarly locked to their respective bars-- -I0 and 25* bypins -30, one of which is projected a slight distance beyond theperiphery of. the adjacent ferrule to form the stud -13 for interlockingengagement in the groove or slot 14. when the parts are adjusted foruse.

It is evident from the foregoing, description that in case a fuse shouldburn out. the

productsof combustion will be confined wholly within the outer casingand if from "this cause or from any other cause the fuse should fail toperform its function as a conductor. the entire device may be withdrawnfrom the contact terminals of the circuit and the fuse holder removedendwise from the outer shell or casing and the fuse repaired. orreplaced as may be necessary after which the fuse holder with the fusethereon may be reinserted into the outer tube or casing and locked inplace by engagement of the stud -13- with the angular slot 14.-, therebyforming a substantially air-tight compart ment in which the fuse islocated, and at the same time establishing reliable electricalconnections with the fuse through contact of the ferrules 8- -8-- and 9-of Figs. 1 and 2 or 22 and -24 of Figs. 6 and 7 hat I claim is:

1. An electric fuse cartridge comprising a tubular shell of insulatingmaterial having electric conducting ferrules rigidly secured on theoutside thereof at its ends and having inturned annular flangesprojecting inside the shell, afuse holder slidable within the ferrulesand shell and provided with contact members of conducting material insliding engagement with the flanges of the ferrules, and a fuse mountedon said holder and electrically connected to said members.

2. An electric fuse cartridge comprising a shell of insulating materialopen at both ends, ferrules of electric conducting material secured onthe outside thereof at the open ends of the, shell and having inturnedannular flanges projecting inside theshell, a fuse holder" movableend'wise into and out of the shell and" providedwith electric conductingmembers in-sliding contact witht-he flanges of the ferrules in theshell, and a fuse on said holder connecting said members.

In witness whereof I have hereunto set my hand on this 18th day of May1911.-

FREDERICK J. FERRARI.

Witnesses: v

H. E. CHASE, E. F. SPEARING.

